Is there any way to determine age according to the case number?

On the older ones the serial is under the dial and demands a disassemble, and for me that means a watchmaker to do the job



When i look at different pocket watches it seems not to match, so movement number is ca. 1912/13 and case number ca. 1915/16 like this one as an example https://omegaforums.net/threads/need-help-on-rare-omega-pocket-watch.50122/ according to the Omega age chart.

Is there better tabels or is there no reel usable connection between case and movement serial number?

I am trying to find the age on this cal. 10''' with case number 5462845

Thanks

 

Hi Thomas. I think you ask two questions. Firstly, regarding the age/date of your watch, I would guess that it’s 1916. That’s largely based on comparison with a 10L wrist that I have (dating 1916).

Turning to your other question (how to date old watches from the caseback number), it is complicated by the fact that both movements and cases were often made in batches – and this can result in some surprising and ‘out-of-sequence’ results. Until about 1935 (case number about 9,000,000), Omega listed and dated watches according to case number – after that point, it was all reversed.

This ‘out-of-sequence’ problem is particularly noticed with some higher-quality movements (example 20’’’DDR) which were often not cased until 10 (even 15!) years later. But again the dating would be according to case number (in this period, which is what you are asking about).

So even if you knew the movement number (of the older watches you refer to), it wouldn’t help to date the watch. The sequence of case numbers will (generally speaking) follow the numerical sequence – often with exceptions!

To be sure – you would need an Extract!
Tom

 

I think the hallmarks on your watch are German (it’s not my speciality) – and if the watch is 1916, that makes it interesting!

David Boettcher’s excellent (vintagewatchstraps) blog will tell you much about hallmarks and might confirm what I write. For example here:
http://www.vintagewatchstraps.com/casemarks.php#swisshallmarks

 

Oh, it gets more complicated! here's my caseback:

 

Oh, 302 numbers apart! Do you have the extract on that one dating to 1916?

I found out the German hallmark were used if the watch were passing through Germany, even if its a Swiss made case.



The G in the German Hallmark could be Geneva

 

Germany 1916: WW1
Don't think they were making many civilians watches...

 

On the subject of serial numbers while we're here. Does anyone know the reason why the sequential serial numbering suddenly got out of order?



Did the ledger keeper at Omega just have a bad New Year's celebration in 1919 and start the 1920 book at 7,000,000 instead of 6,000,000?

Or is it that 1920 is a typo and it should be 1930?

And the same thing with the 9 million serials being applied to 1926 production, not "1936"?

This anomaly is seen in AJTT as well as many other Omega serial references.

I've always wondered why it is. Does anyone have any answers or conspiracy theories?

Cheers
Jim

 

I really think this is a typo Jim (or series of typos). This has been addressed somewhere before (but I'll never find it). And the same data gets extracted/repeated/copied. Tom

 

Thanks Tom, that was my thought's too.

I think the only way to be sure is to order an extract or two from those periods.

 

Jim, I don’t think it’s the only way. Almost all my 7 million movements are in cases with late 7 million or 8 million numbers, and in watches which all date 1930 or after (and didn’t exist in 1920). The same (equivalent) goes for the 9 million movements.

 

+ 1 - I support Tom´s explanation wholeheartedly